JPH03186476A - Decelerating device for electric power steering - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a speed reduction device for an electric power steering device that uses an electric motor to directly assist the driver's steering force, and is particularly suitable for cases where an increase in the torque of the electric motor is required. The present invention relates to a reduction gear for electric power steering.

[Conventional technology]

The conventional reduction gear for electric power steering is JP-A-1-11.
As described in No. 5771, a reduction gear using a hypoid gear and a torque sensor using a Hall element were arranged in the same room.

[Problem to be solved by the invention]

In the conventional electric power steering reduction device described above, the reduction gear consisting of a hypoid gear and hypoid pinion and the detection part of the torque sensor consisting of a Hall element, a magnet, etc. are located in the same room and are close to each other. Iron powder.

There was a problem that it mixed with grease and entered between the Hall element and the magnet, and did not adversely affect the output signal of the torque sensor.

The purpose of the present invention is to solve the above-mentioned problems by creating a structure that isolates the reducer part and the torque sensor so that the torque sensor is not adversely affected by iron powder mixed in grease from the reducer part. An object of the present invention is to provide a reduction gear for electric power steering.

[Means to solve the problem]

The above purpose consists of an upper rotating body that rotates in response to the rotation of the steering wheel, and a lower rotating body that is connected to the upper rotating body via a torsion bar and rotates while producing a torsion angle according to the steering torque. An angle signal or/and torque signal generator attached to each of the upper rotating body and the F section rotating body to detect the rotation angle and 1-lux, and a combination with the angle signal torque and/or signal generating body. A speed reduction device for electric power steering comprising an angle signal and/or torque signal detection body fixed to an outer box for detecting rotation angle and torque, and a speed reduction gear attached to the lower rotary body for transmitting driving force, This is achieved by creating a structure that separates the part where the angle signal Z or/and the 1-lux signal generator and the angle signal Z or/and torque signal detector are arranged from the part where the speed reducer is arranged.

[Effect]

An electric power steering system uses a torque signal detector to detect the torque generated on the steering wheel when the driver applies steering force, and applies a predetermined assist force to the electric motor and clutch according to the detected value. This is a device that is controlled by a control device so that it is generated via a reduction gear to assist the driver's steering force.

Here, the reducer part where the hypoid gear and hypoid pinion mesh, and the torque sensor part where the torque signal generator and torque believer/detector are arranged are isolated from the lower part of the rolling body to which the hypoid gear is screwed. Since the parts are separated and isolated, iron powder generated by the gear meshing of the reducer does not mix with the grease and enter the torque sensor part. Further, due to this isolated portion, there is less scattering of grease, which is a lubricant for the gear, and a sufficient supply of grease is ensured. Furthermore, the lower rotary body to which the hypoid gear is fixed is supported on both sides by this isolated portion, so that the lower rotary body is less bent and the meshing noise of the gears can be reduced.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. An involute spline 2 is cut at the tip of the pinion shaft 1a of the hypoid pinion 1, and meshes with an involute spline 4 of the clutch 3. Further, an angular bearing 5 is press-fitted into the rear end shaft 1b of the hypoid pinion 1, and is tightened with a nut 7 through a washer 6.

Here, the hypoid pinion 1 has a leading end supported by a bearing 9 press-fitted into an outer case 8, and a rear end supported by the angular bearing 5. The axial position of the hypoid pinion 1 is adjusted by a washer 10 inserted into the end of the angular bearing 5, and fixed by tightening a threaded pinion cover 11.

The hypoid pinion 1 i1i meshes with the hypoid gear 12 and constitutes a speed reducer 12a.

Electric motor] 1 Herc of 3 is tl by this reducer L2a
, and the torque is increased.

The hypoid gear 12 is tightened and fixed to the F section rolling body 14 by a screw 15, and the F section rolling body 4 is connected to a torsion bar 16 and a pin 17.

Further, the torsion bar 16 is connected to an upper rotating body 19 by a pin 18 at the upper part.

Here, the lower rotary body 14 has an isolation part 20, and further, an angle and/or torque generator 2]a and a bearing 22a are press-fitted into the isolation part 20. on the other hand,
The upper rotating body 19 is press-fitted with an angle AJ or/and a torque signal generator 21b, and bearings 22b and 23.

Therefore, the above.

The isolation portion 20 separates the torque sensor portion 30a and the reduction gear portion ]-2b.

As described above, the pin 17.1 is inserted through the torsion bar 16.
- part rotary body 9 and lower rotary body 1 connected by 8
4 is supported by the outer case 8 at the upper part by a bearing 22b, and supported by the bearing 25 press-fitted into the outer case 24 at the lower part.

On the other hand, the angle signal or/and torque signal generator 21a,
An angle signal or/and torque signal detector 26 installed parallel to the sensor 21b is fixed to the outer box 8 by a holder 28 via a slider 27 with screws 29, and is protected from the outside by a sensor cover 30b. There is. Further, the angle signal or/and torque signal generator 2], a, 21b
A control device 31 (not disclosed) that controls the electric motor 13 according to the output of a torque sensor 30 consisting of the angle GW and/or the torque signal detector 26 is attached to the box 8.

FIG. 2 is a block diagram of the electric power steering system showing the overall configuration. When a person operates the steering wheel 32 connected to the upper rotating body 19, the angle signal of the l-lux sensor 30 and/or the torque signal detector 26 are detected. Upper rotating body 1
9 and the lower rotating body] 4 is detected as an operating force via the angle signal and/or torque signal generators 21a, 21b, and is transmitted to the control device 31. As a result, the control device 3
1 sends electric power from a battery 33 to electric motor 3 in response to a signal from a torque sensor 30 to drive it.

The torque generated by the electric motor 13 is transmitted via the clutch 3 to the hypoid pinion 1. The force is increased by the speed reducer 12a of the high void gear 2, is transmitted from the lower rotating body 14 to the drive pinion 35 via the universal joint 34, assists the operating force of the steering wheel 32, moves the latch 36, and changes the direction of the tire 37.

According to this embodiment, since the reduction gear part 12b and the torque sensor part 30a are separated by the isolation part 20, iron powder generated due to long-term meshing of the gears of the reduction gear 12a is mixed in the grease and the torque sensor 30 is There is an effect that the performance of the torque sensor 30 can be maintained for a long period of time without intrusion into the vicinity, and therefore high reliability can be ensured.

〔Effect of the invention〕

According to the present invention, since it is possible to have a structure in which the reduction gear part and the first lux sensor part are isolated by the isolation part,
Effects such as those described below can be obtained.

It is possible to prevent iron powder generated by the gear meshing of the reducer from mixing with the grease and entering the 1-Lukunsa portion, and it is possible to improve the performance and reliability of the torque sensor.

Furthermore, it is possible to suppress the scattering of grease, which is a lubricant for the reducer, and improve the durability of the reducer.

Furthermore, by providing the isolation part, the lower rotating body that fixes the gear can be supported on both sides, which reduces bending of the lower rotating body and allows the gears to maintain normal meshing.
Gear meshing noise can be reduced.

In addition, it is possible to block the sound transmitted to the outside, and it is possible to reduce the noise level of the reducer.

[Brief explanation of drawings]

Figures 1 and 2 show one embodiment of the present invention, and Figure 2 is a sectional view of the electric motor, clutch, speed reducer, and torque sensor.
The figure is a configuration diagram of an electric power steering system showing the overall configuration. 12a Reducer, 121]...Reducer part, 14...
Lower rotating body, 16... Torsion bar, 19... Upper rotating body, 21a, 21b... Angle signal y or/and 1-
router signal generator, 26-... angle signal or/and torque tea diagram huaguchi

Claims (1)

[Claims] 1. An upper rotating body that rotates in response to the rotation of the steering wheel; a lower rotating body that is connected to the upper rotating body via a torsion bar and rotates while producing a torsion angle according to the steering torque; and the upper rotating body. An angle signal or/and torque signal generator attached to each of the lower rotary bodies to detect the rotation angle and torque, and in combination with the angle signal and/or torque signal generator to detect the rotation angle and torque. An angle signal and/or torque signal generator in an electric power steering reduction gear comprising an angle signal or/and torque signal detector fixed to an outer box, and a reducer attached to the lower rotating body for transmitting driving force. A reduction gear device for electric power steering, characterized in that it has a structure that isolates a torque sensor part in which an angle signal and/or torque signal detector is arranged, and a reduction gear part in which a reduction gear is arranged.